While Britain experiences an average of seven storms a year, this figure has already been exceeded during what is becoming a tumultuous weather season.
Storm Jocelyn – Britain’s tenth storm in just five months – arrived on Tuesday and continued to batter Britain on its second day with winds of 80mph.
It came just days after Storm Isha, which closed schools, caused power cuts and tragically killed five people in Britain and Ireland.
This was preceded by storm Henk, also in January, and seven other storms that have also hit the British Isles since the beginning of September.
So why are we hit by so many of these stormy weather events? MailOnline goes into more detail.
Although the position and altitude of the jet stream changes, it moves at a similar level to that of transatlantic aircraft. The jet stream carried low-pressure systems across the Atlantic Ocean to Britain, causing the high-speed winds and undesirable weather typical of storms
Storm Jocelyn has caused dangerous conditions and new travel disruptions across much of Britain. Pictured: Waves crashing onto the beach at New Brighton, Wirral
According to the Met Office, the term ‘storm’ has no official meteorological definition, but is used to describe ‘a deep and active area of low pressure and associated strong winds and precipitation’.
It is said that the main cause of the recent storms is the jet stream – a fast-moving band of air about five to ten miles above the Earth’s surface.
The jet stream blows from west to east at a speed of more than 160 kilometers per hour.
“The jet stream has a major impact on the weather we experience in Britain and in recent months it has largely been focused on Britain and Ireland,” said Met Office meteorologist Annie Shuttleworth.
‘These systems are focused on Britain and have eventually become storms due to the strong winds and heavy rain they bring.’
The power of the jet stream has been amplified by a recent series of events.
About two weeks ago, a pool of frigid air sank south over North America, where the jet stream originates over Britain.
When the cold air hit warmer subtropical air, the temperature contrast strengthened the jet stream, said Jim Dale, senior meteorologist at British Weather Services.
A stream of fast-moving air, the jet stream (coloured pink), is currently flowing across Britain
‘The collision of these opposing air masses strengthened the upper airflow, which then carried low-pressure systems into and across the Atlantic Ocean,’ he told MailOnline.
These ‘low pressure systems’ exist as spinning vertical vortices between the ground and the jet stream.
They are known as low-pressure areas because the atmospheric pressure is lower than the pressure of surrounding locations.
As a result, ambient air begins to flow in in an attempt to equalize the pressurecreating the high speed winds and undesirable weather typical of storms.
According to Dale, the original event that caused North America’s frigid air to move south may have been related to climate change.
It has to do with the polar vortex – an atmospheric circulation pattern located high above the poles in the stratosphere.
“The polar vortex is moved by the sudden warming of the stratosphere caused by chaotic atmospheric waves,” Dale said.
‘This disrupts the normal anticyclonic motion over the pole, allowing very cold air at the surface to flow southwards towards the Americas (in this case), Europe or Asia.’
Studies have already linked climate change to high-intensity weather events such as storms, floods, droughts and forest fires.
Storms are thought to become more intense as warmer surface temperatures increase wind speeds.
“Climate change is part of that equation,” Dale told MailOnline. “It’s happening and it’s not a figment of our imagination.
A fallen tree lying in the water after the banks of the River Ouse burst following Storm Jocelyn, January 24
Workers remove a tree that fell on an electricity substation on the Kinnaird estate in Larbert during Storm Isha on Sunday
“This and the various extreme events we have experienced over the past five to six years are just the beginning.”
Melissa Lazenby, a meteorologist at the University of Sussex, said human influence was “changing the usual patterns of British storms and will continue to do so in the future.”
‘There is consensus among models that the frequency of winter storms is expected to increase, as well as associated wind speeds and rainfall,’ she told MailOnline.
“It is also highly likely that the intensity of these winter storms will increase and rainfall from these events will result in greater impacts such as flooding and greater storm surges along coastal areas.
“Additional adaptation and mitigation measures will be needed to mitigate their impacts, such as flooding and storm surges.”
At the start of each September, the Met Office reveals its list of names for upcoming storms, if and when they occur over the next twelve months.
Storm Jocelyn is the tenth storm named since September 1, 2023 by the Met Office’s storm naming group, which also includes Met Eireann and the KNMI
The Met Office started naming storms in 2015. In the last storm season (2022/23) there were only two storms (both in August). The 2015/16 season saw 11 storms – more than any other. But with ten storms before the end of January, this season (2023/24) could surpass that total
The first storm of the 2023/24 season, named Storm Agnes, arrived on September 27-28, 2023. Pictured is Storm Agnes’ rotating vortex low-pressure system over the British Isles.
These names are arranged alphabetically, so the first one in gets a name starting with A, the second with B, and so on.
For the 2023/24 storm season, the first storm was called Agnes – which also hit parts of Great Britain and Ireland – the second was called Babet and the third was Ciarán.
It is an effective system because the name of the storm and the time it occurs immediately show how productive a storm season is.
2023/2024 will mark only the second time in a British storm season that it will reach the letter J in the alphabet.
Last year’s storm season, which ran from September 2022 to August 2023, only reached the letter B, with Storm Antoni and Storm Betty, both in August.